This invention relates to improved direct current operated starting motors. More particularly, the invention relates to an improved brush plate assembly useful as a component in direct current operated starting motors.
Starting motors, e.g., associated with transportation vehicles, often operate off a direct current power source, e.g., battery. Such motors have a brush armature combination to provide the necessary rotation. Often, these motors have a brush plate assembly which contains a brush plate and a plurality of brush holders secured to the plate. In turn, the plate may be provided with an insulating plate and a support.
Direct current power is supplied to the brush plate by an elongated stud which is in electrical communication with a direct current power source. Conventionally, the brush plate and elongated stud are manufactured as a single unit.
During maintenance of the starting motors described above, the elongated stud of the brush plate assembly is particularly vulnerable to damage and may be broken from the remainder of the assembly. In the past, when such damage did occur, the entire brush plate assembly had to be discarded or, at best, disassembled in order to replace the elongated stud brush plate part. This, in turn, resulted in increased maintenance time and parts costs to the consumer. Clearly, it would be advantageous to reduce the time and material needed to repair a starter motor in the event of damage to the elongated stud.
Therefore, one object of the present invention is to provide an improved brush plate assembly.
An additional object of the invention is to provide a brush plate assembly for use in direct current operated starting motors which has improved maintenance characteristics. Other objects and advantages of the present invention will become apparent hereinafter.
An improved brush plate assembly has now been discovered. The assembly, for use in a direct current operated starter motor comprises a brush plate having a plurality of brush holders secured to it, and an elongated stud member removably secured to the brush plate and acting to provide electrical communication between a direct current source and the brush plate. An important characteristic of the present invention is that the elongated stud member be removably secured to the brush plate. That is, the present stud member and brush plate are separate components which are secured to each other and can be separated. In the event that the stud member is broken, or otherwise damaged, the stud can be removed from the brush plate and replaced by a different elongated stud without disturbing or disassembling the other components, e.g., brush holders and associated parts of the brush plate assembly. This reduced or simplified maintenance procedure for the brush plate assembly results in savings of time, labor and materials expense. For example, damage to the present elongated stud member may not result in the time consuming and wasteful replacement of the entire brush plate assembly.
One additional feature of the present invention involves fitting used brush plate assemblies with removable elongated stud members. For example, as noted previously, conventional brush plate assemblies are marketed so that the elongated stud and brush plate together form one part. When the elongated stud is broken off along its length or otherwise damaged, the entire brush plate assembly has been discarded. The present invention envisions efficiently restoring such damaged brush plate assemblies to full usefulness. Thus, the damaged elongated stud, cut, or otherwise separated, from the brush plate at or near the plane of the plate leaves an uneven surface at or near the plane of the brush plate which may be ground, polished and the like to provide improved electrical conductivity at such surface. After the damaged elongated stud has been separated from the brush plate, an elongated stud member according to the present invention is removably secured to the brush plate at or near such surface. Thus, the conventional brush plate assembly with a single part elongated stud brush plate can be restored or reworked into an assembly with a removable elongated stud member. Such restoration and/or reworking is within the scope of the present invention.
The brush plate assembly of the present invention preferably further includes at least two threaded screws for each brush holder. These threaded screws act to secure the brush holders to the brush plate.
In one preferred embodiment, the brush plate has two holes therethrough and the elongated stud member includes a base which also has two holes through it. The base of the elongated stud member is in contact with the brush plate so that the holes of the base are substantially aligned with the holes through the brush plate. These substantially aligned pairs of holes each receive one of the threaded screws, noted previously. Also included, in association with the base, is a nut means which abuts each of the base holes and acts to hold the threaded screws securely in the pair of substantially aligned holes. As noted above, this is a preferred embodiment by which the elongated stud member is removably secured to the brush plate.
These and other aspects and advantages of the present invention are set forth in the following detailed description, particularly when considered in conjunction with the accompanying drawing in which like parts bear like reference numerals.